Myocardial tissue viability is currently characterized by either analysis of electrograms (EGMs) or by non-invasive imaging modalities such as echocardiography and delayed enhancement MRI (DE-MRI). However, these imaging methods may have limitations. For example, echocardiography is an indirect measure of infarcted tissue and suffers from intra-observer and inter-observer variability. DE-MRI carries high costs, and device compatibility remains an issue not completely resolved. Also, EGMs provide inferential information based on a fractionated signal and is limited by the number of sites covered. Left ventricular lead implantation requires the lead to be placed accurately in a coronary vein that leads to optimal benefit and does not compromise the safety of the patient. For example, a left ventricular lead implant near or at an infarct zone may lead to non-efficacious pacing due to the electrical inactively of the non-viable tissue. In one example, the goal may be to pace at or near the site of a scar tissue.
Ablation for scar-related/ischemic ventricular tachycardia is a technique that requires precision in the location of the lesion creation. It is typically guided by electro-anatomical mapping. However, the mechanical component of information from the chamber is not taken into account. Thus, there is a need to improve the accuracy of substrate characterization and localization and provide guidance on decision making in regard to ablation or cardiac resynchronization therapy (CRT) lead implant location, for example, with respect to infarct scar zones.